A specially designed column for high pressure liquid anion chromatography with UV-absorption was used to compare the modified nucleosides and/or bases in tRNAs from normal monkey liver and hepatoma. In addition, degradation products found in urine e.g., Beta-aminoisobutyric acid will be determined for respective normal and hepatoma monkeys as well as other associated excretion products e.g., methylated nucleosides, pseudouridine and polyamines. These studies are being carried out to gain information as to changes in tRNA associated with tumors and the reflection of these changes as noted by their urinary excretion products and levels.